The internet classics archive:
an incredibly useful resource. The text of the Iliad is here in its entirety, and the site has an excellent search engine that can shave hours off of writing papers. If you are looking for a specific line or need to read every part of the poem that concerns Diomedes, this is the place to go.
The Greek Mythology Link, an incredible site:
http://homepage.mac.com/cparada/GML/
Well-designed, informative, and fun, the Greek Mythology Link is a tremendous resource for getting background information on the Iliad. Included are maps, biographies of important heroes and deities, and a search engine. Use the map resources to find the homes of the different contingents.
A site with valuable links
for gathering information on Homer and the ancient Mediterranean. Not all of the links actually work, but be patient. There's valuable material here, as long as you're patient enough to find it. For starters, follow the link that says "Troy: Homer and the Troy Cycle." It's no the right hand side, near the top of the page.